Final answer:
Finding native workers was a challenge for colonists in the Americas due to decimation of native populations by European diseases, native resistance to enslavement, and the small and scattered native populations.
Step-by-step explanation:
The challenge for colonists to find native workers in the Americas was due to several factors. One reason was that European diseases decimated native populations, making it difficult to find enough healthy workers. Another factor was that native workers often resisted enslavement, escaping and hiding in the vast land. Additionally, the native populations were small and scattered, making it challenging to locate and recruit them for labor.